Fix bug on MD380

Fixed a bug where pressing the side button would lead to a crash,
probably caused by a misaligned memory access, due to the addition of a
packed attribute.

openrtx/include/ui.h

@@ -136,8 +136,7 @@ typedef struct layout_t
     fontSize_t bottom_font;
     fontSize_t input_font;
     fontSize_t menu_font;
-}
-__attribute__((packed)) layout_t;
+} layout_t;
 
 /**
  * This structs contains state variables internal to the